Introducing a numeral called dec

There are nine familiar numerals in base-12 math, and two extra numerals called dec and el, and they were all designed by the same person, or group of people, using the same mathematical and geometric logic. In this video I explain why the numeral called dec has the design that it does, containing the value of the number that it is meant to represent, while also being attached to the tenth circle in the concentric square root radius circle series - the circle with the radius √10.

It is important to note that ALL the numerals share the characteristic of being attached to their corresponding circle in this series of circles, while also containing within their design the value of the number they are meant to represent.